Forum Discussion

SmithRV's avatar
SmithRV
Explorer
Oct 03, 2016

Transmission Programming

Hello. I own a Winnebago Grand Tour Vectra 1997 With a 250 HP Cat Engine and a Freightliner chassis Model: WKM35WQ. I tow a Jeep Wranglar X Unlimited with a Blue Ox package. From many peoples reviews on my other topic it seems my Transmission is not programmed for towing it. So where can I go to get my transmission or something inside the engine to realize that it needs to adjust gears according to a jeep also. It's only programmed to move the RV not the jeep with it. I kinda figured this out because I went to Catapillar and they brought a computer out with wires in the dash and some going all the way back to the engine, and he made me drive and said everything checked out, and my transmission was fine but I also realized that it was doing fine when usually going up a grade is bad. So I left all good but then it happened again when towing my jeep and going up a grade my RV won't gear down my RPMS drop somewhat and then my speed will drop a huge amount usually from 70 to 40 but I fix this by manually dropping the gears from 5th or 6th down to the 4th or 3rd gear and then going up a hill is great I can go up a hill around 50 or 60 sometimes. But my question is, is my transmission failing ir does it need to be calibrated to tow a jeep?
Class A
  • usersmanual's avatar
    usersmanual
    Explorer
    Oct 04, 2016
    Kayteg1 wrote:
    Toad or not, older vehicles had kick-down switch under gas pedal, newer do it electronically, but when you push the pedal to the floor at lower rpm, the transmission has to downshift.
    Id it is not doing that, it needs service.
    On vehicles having tow mode, most of the time it will prevent from going to overdrive and help with engine braking.
    Did not hear about towing program affecting downshifting.


    this is a 6 speed Allison diesel pusher trans he asking about not a gasser ford or GM style MH
  • Kayteg1's avatar
    Kayteg1
    Explorer II
    Oct 04, 2016
    Toad or not, older vehicles had kick-down switch under gas pedal, newer do it electronically, but when you push the pedal to the floor at lower rpm, the transmission has to downshift.
    Id it is not doing that, it needs service.
    On vehicles having tow mode, most of the time it will prevent from going to overdrive and help with engine braking.
    Did not hear about towing program affecting downshifting.
  • usersmanual's avatar
    usersmanual
    Explorer
    Oct 03, 2016
    SmithRV wrote:
    Hello. I own a Winnebago Grand Tour Vectra 1997 With a 250 HP Cat Engine and a Freightliner chassis Model: WKM35WQ. I tow a Jeep Wranglar X Unlimited with a Blue Ox package. From many peoples reviews on my other topic it seems my Transmission is not programmed for towing it. So where can I go to get my transmission or something inside the engine to realize that it needs to adjust gears according to a jeep also. It's only programmed to move the RV not the jeep with it. I kinda figured this out because I went to Catapillar and they brought a computer out with wires in the dash and some going all the way back to the engine, and he made me drive and said everything checked out, and my transmission was fine but I also realized that it was doing fine when usually going up a grade is bad. So I left all good but then it happened again when towing my jeep and going up a grade my RV won't gear down my RPMS drop somewhat and then my speed will drop a huge amount usually from 70 to 40 but I fix this by manually dropping the gears from 5th or 6th down to the 4th or 3rd gear and then going up a hill is great I can go up a hill around 50 or 60 sometimes. But my question is, is my transmission failing ir does it need to be calibrated to tow a jeep?

    your posts are confusing and hard to believe.You said in the last section your rpm @60MPH stayed at 2000 but then your speed dropped to 40MPH and it was till @2000 now your saying your RPM will drop somewhat when the speed drops I seriously can not see this little 250HP unit going up a hill towing in 4th gear at 60 MPH
    I believe you are expecting more than what this overloaded underpowered unit will do.
  • rgatijnet1's avatar
    rgatijnet1
    Explorer III
    Oct 03, 2016
    SmithRV wrote:
    Ok and yes it is an Allison Trans.


    An Allison certified shop will be able to tell you if the transmission is working properly or not. It sounds like the erratic operation may indicate a problem but they should have the equipment to give you a complete diagnosis. I had Brazel's RV reprogram my Allison transmission along with my ECM.
  • wallynm's avatar
    wallynm
    Explorer
    Oct 03, 2016
    So tell me at what RPM do you expect the transmission to downshift ans how fast do you expect to go up a 3 to 5% grade?

    SmithRV wrote:
    Hello. I own a Winnebago Grand Tour Vectra 1997 With a 250 HP Cat Engine and a Freightliner chassis Model: WKM35WQ. I tow a Jeep Wranglar X Unlimited with a Blue Ox package. From many peoples reviews on my other topic it seems my Transmission is not programmed for towing it. So where can I go to get my transmission or something inside the engine to realize that it needs to adjust gears according to a jeep also. It's only programmed to move the RV not the jeep with it. I kinda figured this out because I went to Catapillar and they brought a computer out with wires in the dash and some going all the way back to the engine, and he made me drive and said everything checked out, and my transmission was fine but I also realized that it was doing fine when usually going up a grade is bad. So I left all good but then it happened again when towing my jeep and going up a grade my RV won't gear down my RPMS drop somewhat and then my speed will drop a huge amount usually from 70 to 40 but I fix this by manually dropping the gears from 5th or 6th down to the 4th or 3rd gear and then going up a hill is great I can go up a hill around 50 or 60 sometimes. But my question is, is my transmission failing ir does it need to be calibrated to tow a jeep?
  • hanko's avatar
    hanko
    Explorer
    Oct 03, 2016
    well this is a first. Are you sure some one isn't pulling your leg
  • rgatijnet1's avatar
    rgatijnet1
    Explorer III
    Oct 03, 2016
    If your transmission is an Allison, I would think most Allison certified shops could take care of it.

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